Flaxseeds, chia seeds, walnuts, hemp seeds, and soybean products are among the richest non-fish sources of omega-3 fatty acids. Most plant foods deliver omega-3 in the form of ALA (alpha-linolenic acid), which your body handles differently than the EPA and DHA found in seafood. The good news: you can meet your daily omega-3 needs entirely from plant sources, and one option, algal oil, gives you the same EPA and DHA as fish without the fish.
Seeds: The Most Concentrated Plant Sources
If you’re skipping fish, seeds are your best starting point. Flaxseeds top the list. About 50% to 60% of the fat in flaxseeds comes from ALA, making them one of the most omega-3-dense foods on the planet. A single tablespoon of ground flaxseed delivers roughly 1.6 grams of ALA, which alone meets the daily adequate intake for adult women (1.1 grams) and hits the target for adult men (1.6 grams). Flaxseed oil is even more concentrated, though it comes without the fiber benefits of whole ground seeds.
Chia seeds are another strong option, packing around 1.6 to 1.8 grams of ALA per tablespoon depending on the variety. They’re easy to add to smoothies, oatmeal, or yogurt, and unlike flaxseeds, they don’t need to be ground for your body to absorb the nutrients.
Hemp seeds (often sold as “hemp hearts”) contain ALA too, but noticeably less. Only about 15% to 26% of the fat in hemp seeds is ALA, compared to flaxseeds’ 50% to 60%. Hemp hearts are still nutritious, offering a good balance of protein and healthy fats, but they’re not in the same league as flax or chia for omega-3 specifically.
Walnuts Stand Out Among Nuts
Walnuts are the only common tree nut with a meaningful amount of omega-3. A standard one-ounce serving (about 14 walnut halves) provides roughly 2.5 grams of ALA. Even a smaller 25-gram portion delivers around 1.9 grams, well within the daily recommended range. No other popular nut comes close. Almonds, cashews, and pecans have trace amounts at best.
Walnuts are also versatile. Toss them into salads, blend them into pesto, or just eat a handful as a snack. Because the ALA in walnuts is relatively stable at room temperature, you don’t need to worry about special storage the way you do with flaxseed oil.
Soybeans, Edamame, and Tofu
Soy-based foods are a reliable omega-3 source, particularly for vegans and vegetarians who eat them regularly. A half cup of prepared edamame contains about 0.28 grams of ALA. That’s modest compared to seeds or walnuts, but soy shows up in many forms throughout the day: tofu, tempeh, soy milk, miso. Those servings add up. Soybean oil, commonly used in processed and restaurant foods, also contributes ALA to the average diet, often without people realizing it.
Cooking Oils That Provide Omega-3
Flaxseed oil and walnut oil are the two richest omega-3 cooking oils, but they come with an important limitation: heat destroys their omega-3 content. Flaxseed oil has an extremely low smoke point of about 225°F, meaning it should never be used for cooking. It works well drizzled over finished dishes, blended into smoothies, or whisked into salad dressings. Walnut oil is slightly more heat-tolerant at around 320°F (unrefined) but is still best used cold or at very low temperatures.
Canola oil and soybean oil contain less ALA per tablespoon but tolerate higher cooking temperatures, making them more practical for everyday use. If you sauté vegetables in canola oil and dress your salad with flaxseed oil, you’re covering both bases.
The ALA Conversion Problem
Here’s the catch with plant-based omega-3: your body needs to convert ALA into EPA and DHA, the two forms that play the biggest roles in heart health, brain function, and reducing inflammation. That conversion is inefficient. Healthy adults convert only about 5% to 10% of ALA into EPA and just 2% to 5% into DHA. Some estimates put it even lower, at less than 5% total for both.
This doesn’t mean plant-based ALA is useless. ALA has its own health benefits, and eating enough of it still supports overall omega-3 status. But if you’re specifically trying to raise your EPA and DHA levels without eating fish, relying on flaxseeds and walnuts alone may not be enough.
Algal Oil: Plant-Based EPA and DHA
Algal oil is the one non-fish source that provides EPA and DHA directly, skipping the conversion bottleneck entirely. It’s derived from microalgae, which is actually where fish get their omega-3 in the first place. Fish accumulate DHA and EPA by eating algae (or eating smaller organisms that ate algae), so algal oil cuts out the middleman.
A 2025 clinical trial compared plasma levels of DHA and EPA in adults taking either microalgal oil or fish oil supplements over 14 weeks. The algal oil was statistically non-inferior to fish oil for bioavailability of both DHA and EPA. In practical terms, your body absorbs and uses algal oil omega-3 just as well as the fish-derived version. Algal oil supplements are widely available in capsule and liquid form, typically providing 250 to 500 milligrams of combined DHA and EPA per serving.
Fortified Foods Worth Checking
A growing number of everyday grocery items are now fortified with omega-3. You’ll find it added to certain brands of eggs (from hens fed flaxseed or algae), yogurt, milk, soy beverages, and even orange juice. The omega-3 content varies widely by brand, so checking the nutrition label is the only way to know how much you’re actually getting. Omega-3 enriched eggs typically contain 100 to 150 milligrams of DHA per egg, which is a useful boost on top of other dietary sources.
Fortified foods alone probably won’t meet your full omega-3 needs, but they’re a convenient way to increase your intake without changing your routine.
How Much You Actually Need
The current adequate intake for ALA is 1.6 grams per day for adult men and 1.1 grams per day for adult women, with slightly higher targets during pregnancy (1.4 grams) and breastfeeding (1.3 grams). These recommendations apply specifically to ALA because it’s the only omega-3 officially classified as essential. There’s no separate federal intake recommendation for EPA or DHA, though many health organizations suggest 250 to 500 milligrams of combined EPA and DHA daily for general health.
Meeting the ALA target from plant foods is straightforward. A tablespoon of ground flaxseed or a small handful of walnuts gets you there. If you also want meaningful EPA and DHA without fish, an algal oil supplement is the most direct route. Combining both strategies, a diet rich in seeds, nuts, and soy alongside an algal oil supplement, gives you comprehensive omega-3 coverage without any seafood on your plate.